I really wish he'd worked out the dating system earlier on. It would have added so much more depth to the game beyond fetch quests and following the phone walkthrough, and he could have added small bits to build up multiple characters rather than trying to get out entire storylines in one massive chunk. The sex scenes are great, but I really love all the little interactions you get when you take characters out into the world and see them bounce off one another. So much of Roxxy's charm comes from seeing her slagging on Becca/Missy, getting into fights with Eve, or rolling her eyes at Dexter. I think Judith would have won her poll a lot earlier if we'd gotten to know her outside of just blushing at the MC or being the buttmonkey of the sexy situation du jour.
I honestly don't think the dating system would have impacted the order that much. We have to remember that it's still a porn game and that people want to see actual scenes for characters that get content in an update. In most cases you simply need the full story to add NSFW content for the girls - unless of course we are talking about stuff like voyeurism, which is kinda boring in 99 % of the cases. It's pretty hard to add larger amounts of normal content for any character, without adding at least a bit of lewd stuff somewhere for them, too.
I'd agree though that the dating should have been added earlier - then again, it's great that now there's a chance to get new locations, etc. and to set everything up properly. If he had added in back in 2017/2018, there probably would have been a lot to rework, too.
Trying to shoehorn it into a late-stage game is going to be a pain and a half, too. Lord knows we don't get enough complaints about save compatibility as is, and I wouldn't be shocked if it results in another long dev fiasco unless they're laying the groundwork for it as part of the Tech Update. Here's hoping, anyways.
Ultimately it'll simply cut the stories as they are now "in half". In Roxxy's case MC will beat Dexter and instead of meeting her in the trailer in the evening and visiting the beach on saturdays, he'll have to date her first to get these scenes and to unlock the prom.
At least I would hope, that they are considereing these things now when they are writing the stories for Ronda, Annie, Judith, etc.